title: Immunocytochemistry of GLUT2, uptake of fluorescent desnitroso-streptozotocin analogs and phosphorylation of D-glucose in INS-1E cells.
abstract: The non-invasive imaging of GLUT2-expressing cells remains a challenge. As streptozotocin, and similarly alloxan, may be transported into cells by GLUT2, the major aim of the present study was to assess the possible use of fluorescent desnitroso-streptozotocin analogs for in vitro labeling of GLUT2-expressing cells. INS-1E cells, human embryonic kidney (HEK) cells, rat isolated pancreatic islets, rat hepatic cells, rat exocrine pancreatic cells and tumoral insulin-producing BRIN-BD11 cells were incubated in the presence of two distinct fluorescent desnitroso-streptozotocin analogs, probes A and B. The immunocytochemistry of GLUT2 in INS-1E cells and the phosphorylation of D-glucose by INS-1E cell homogenates were also examined. The uptake of probes A and B (12.0 µM) by INS-1E cells yielded apparent intracellular concentrations approximately one order of magnitude higher than the extracellular concentration. The two probes differed from one another by the absolute values for their respective uptake and time course, but not so by the pattern of their concentration dependency. Comparable results were recorded in HEK cells, rat isolated pancreatic islets and hepatocytes. Vastly different findings were recorded, however, in rat exocrine pancreatic cells, which do not express GLUT2. Moreover, an unusual concentration dependency for the uptake of each probe was observed in tumoral BRIN-BD11 cells. It is proposed that suitable fluorescent desnitroso-streptozotocin analogs may be used to label GLUT2-expressing cells.
authors.affiliation: Laboratory of Cell and Molecular Physiology, Université Libre de Bruxelles, Brussels B-1070, Belgium.
authors.forename: Myrna
authors.initials: M
authors.lastname: Virreira
authors.forename: Iuliana
authors.initials: I
authors.lastname: Popescu
authors.forename: Celine
authors.initials: C
authors.lastname: Gillet
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yevgeniy
authors.initials: Y
authors.lastname: Leshch
authors.forename: Julian
authors.initials: J
authors.lastname: Thimm
authors.forename: Joachim
authors.initials: J
authors.lastname: Thiem
authors.forename: Willy J
authors.initials: WJ
authors.lastname: Malaisse
authors.forename: Abdullah
authors.initials: A
authors.lastname: Sener
mesh_terms: D000818:Animals; D002460:Cell Line; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D051273:Glucose Transporter Type 2 / Q000235:genetics / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D007515:Islets of Langerhans / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D013311:Streptozocin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D051273:Glucose Transporter Type 2; D013311:Streptozocin; D005947:Glucose